In the manufacture of wings for large aircraft, the wing components, including the wing skin panels, the spars, the ribs and other major components are typically partially assembled in a jig. Holes for fasteners are then drilled in predetermined locations. Slave bolts are then inserted in some of the holes and dowels inserted in others to hold the wing assembly together whilst further holes are drilled. Thereafter the bolts are unfastened and the components disassembled, for example, to allow deburring to be carried out, before they are finally reassembled.
In order to drill the further holes in the correct positions, it is common to use either a manual template arrangement or to use an automatic drilling machine. When a manual template is used, a template is placed over one or more of the slave bolts and is held in the correct, fixed position by the engagement with the slave bolts. When an automatic drilling machine is used, however, the heads of the slave bolts provide visual reference points for the machine which after drilling a hole is moved over the components to another position for drilling another hole.
When a template is used as described above, it is desirable that a head of the slave bolt projects a substantial distance outwards from the components to provide a good physical location for the template. On the other hand, when an automatic drilling machine is employed, it is desirable that the bolt projects only a very limited distance so that the drilling machine can travel over the bolt in close proximity to the components. In order to meet those two conflicting requirements it has in the past been necessary to provide two different slave bolts.
It is an object of the invention to provide a fastener assembly that is adaptable for use with both a template and an automatic drilling machine.